Category:614 Drainage Fittings (Grate Inlets)

There are many aspects to be considered when inspecting construction quality and this article provides material inspection guidelines. For Laboratory testing and sample reporting procedures, refer to 614.3 Laboratory Testing Guidelines for Sec 614.

Two types of inlet grates are shown in the standard plans. The curved vane grate (Standard Plan 614.11) is used in roadway and shoulder applications and is considered bicycle safe. The parallel bar grate (Standard Plan 614.10) may be used only in areas outside the roadway and shoulders, such as in grassy medians or other unpaved areas.

Standard curved vane grate inlets are 2 ft. long (measured in the direction of flow), and either 2 or 4 ft. wide (measured perpendicular to the direction of flow). Only 2 ft. wide inlets may be used in curb and gutter sections; whereas 2 or 4 ft. widths may be used with integral curb (triangular) sections. Details of the inlet grates and gutter cross-sections may be found in the standard plans.

Grate inlets fit in Type S-1, S-2 or S-3 precast drop inlets. Precast drop inlet covers, Types A, B, C, D and E, are shown in the standard plans.

Hydraulic aspects of grate inlets are presented in 640.1 Pavement and Bridge Deck Drainage.

614.1 Construction Inspection Guidelines for Sec 614

Manhole Frame And Cover And Curb Inlet (for Sec 614.30). The Standard Plans are clear.

614.2 Maintenance of Floodgates

Flood gates installed by MoDOT shall be maintained by MoDOT regardless of the reason for the installation. Flood gates installed by others shall be maintained by the installer unless the department has agreed to maintain the flood gate through written agreement. The standard contract form MT-16 MISSOURI HIGHWAYS AND TRANSPORTATION COMMISSION CULVERT FLOOD GATE AGREEMENT shall be used when establishing maintenance responsibilities for a flood gate.